Sub-Saharan Africa is characterized by high absolute rates of HIV/AIDS infection and high rates of new infections. There are approximately 16.6 million AIDS orphans (children who have lost one or both parents to HIV/AIDS), 14.8 million of whom live in sub-Saharan Africa1. These orphans and vulnerable children (OVC) are the focus of the proposed work. Specifically, we intend to work in Zambia, a sub-Saharan country with high rates of infection and as many as 600,000 children orphaned by HIV/AIDS and another 150,000 (ages 0-14) living with HIV/AIDS. Rather than focusing on specific OVC interventions, we will focus on all interventions administered within a 25km radius of a well-established regional hospital, Macha Mission Hospital (MMH), to assess their effects on the OVC in the area. We will do this in two steps. First, we will construct a representative sample of ~1,000 OVC, ages 7-17, and characterize them using an array of well-defined indicators that focus on their health, well-being, and cognitive, academic, and adaptive functioning. This characterization will be longitudinal, with at least 3 time points for each individual. Second, we will identify and characterize all interventions that are delivered to these OVC, first via information from the OVC themselves and their caregivers, then by surveying the providing organizations. Using a mixed-method design, we will assemble qualitative and quantitative evidence, describing key components of the existing programs to differentiate, at least preliminarily, the effectiveness of the present interventions. We hypothesize that interventions with a strong component aimed at safeguarding OVC access to continuous schooling of adequate quality will stand out as most promising with respect to ensuring OVC's developmental potential.